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Imagine a net so fine, it's invisible to the naked eye.

But this isn’t just any net - it’s an electrical barrier. With every breath you take, faint electric sparks dance across its nanoscale fibers. The moment a pathogen touches the net, it’s instantly incapacitated, unable to repair its cell membrane before being completely neutralized.

Sounds like science fiction? Think again.

Sim Moh Terng, a final-year master’s student at the School of Energy and Chemical Engineering, Xiamen University Malaysia (XMUM), has spent three years turning this vision into reality. Together with his team, Sim Moh Terng has developed a revolutionary face mask that integrates this electrical barrier into a self-disinfecting design, powered entirely by the wearer's breath.

Unlike conventional masks that passively "trap" pathogens, this cutting-edge mask acts swiftly and actively to neutralize them. Its secret lies in harnessing the power of breathing to generate electricity.

Illustration of the respiration-driven antimicrobial face mask and the working mechanism of R-TENG. (Source: Sim et al., https://doi.org/10.1002/adfm.202410062)

Sim Moh Terng's research demonstrates how the friction from air movement during breathing drives thin films inside the mask to rub against each other, producing energy through the triboelectric effect. This phenomenon occurs when two materials make contact and then separate, generating electricity.

To optimize the process, Sim Moh Terng’s design incorporates a curved membrane structure that maximizes the surface area for friction. Each breath compresses and separates the membranes, creating a voltage of up to hundreds of volts. This energy enhances the electric field in the mask's filter layer, making it a powerful "defense" against pathogens.

This groundbreaking innovation transforms every breath into an active force for protection, combining the simplicity of a face mask with the sophistication of nanoscale technology.

Once activated, the electric field within the mask's filter layer transforms nanowires into microscopic fencing, capable of piercing pathogen membranes through a process known as electroporation. This disables the pathogens, leaving them unable to repair themselves.

This self-powered face mask leverages the energy from human breathing to neutralize pathogens continuously, eliminating the need for an external power source, explains Sim Moh Terng. Its high-efficiency protection is particularly beneficial for healthcare workers in remote areas.

Animation of R-TENG-powered electroporation for instant disinfection. (Source: Sim et al., https://doi.org/10.1002/adfm.202410062) 

The work was inspired from the challenges of the COVID-19 pandemic. In 2021, as Malaysia grappled with rising cases, soaring face mask prices, and overwhelmed healthcare workers, Sim Moh Terng, then a senior student, sought to apply his research on triboelectric nanogenerators to create a practical, self-cleaning face mask.

Existing self-disinfecting masks had limitations - they required hours to sterilize or relied on external power sources, which were cumbersome and prone to cross-contamination. Recognizing the potential of electroporation, a proven disinfection method in water sterilization, Sim Moh Terng embarked on a three-year journey with his team to integrate this technology into a mask.

The mask's significant innovation lies in generating electricity through friction. Using durable and electricity-generating materials - polyvinyl alcohol (PVA) and polyvinylidene fluoride (PVDF) - the team designed a dome-shaped membrane system to maximize surface contact and voltage output. Each breath compresses and separates the layers, producing energy via the triboelectric effect.

A 3D printer was used to create the dome structure, while copper hydroxide nanowire filters - 100 times thinner than a human hair - formed the disinfection layer. This design allows the mask to generate up to 120 V from steady breathing, powering its electroporation mechanism.

Electrical outputs of R-TENG at various frequencies. (Source: Sim et al., https://doi.org/10.1002/adfm.202410062)

To test the mask's efficacy, the research team utilizing the Bacillus subtilis, a bacterium known for its resilient spores. The mask was evaluated in three configurations: without the nanowire filter or electricity, with the filter but no electricity, and with both the filter and electricity. The fully powered mode achieved a 99.9% pathogen kill rate. The mask's durability and consistent disinfection capabilities was tested under various conditions.

Weighing just around 60 grams - about as much as a chocolate bar - the mask provides effective protection and is compact enough for daily use. Although still in the experimental phase, the team envisions applications extending beyond healthcare to industrial and environmental sectors, offering self-powered respiratory protection in diverse scenarios.

Disinfection performance of R-TENG-powered electroporation filter. (Source: Sim et al., https://doi.org/10.1002/adfm.202410062) 

The study's results, published in Advanced Functional Materials under the title Instant Disinfecting Face Masks Utilizing Electroporation Powered by Respiration-Driven Triboelectric Nanogenerators, mark a significant step toward integrating advanced technology into daily life.

This innovation is a testament to how a simple act like breathing can drive groundbreaking solutions for global challenges.

The research team: (1st row, from left) Ee Zhi Yin, Sim Moh Terng, Sia Tee Sheng; (2nd row) Dr. Tan Swee Tiam, Dr. Gan Wee Chen